• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.80-84
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• 2000

To investigate the effect of packaging condition on functional MA films laminated (30CE, 50CE), corrugated paperboard box (control), 30LDPE, and 50LDPE pouches on the freshness extension of Fuji apples, the weight loss, firmness, total ascorbic acid, titratable acidity, soluble solids content and appearence were evaluated at 5$^{\circ}C$ after 75 days. Weight loss of 30CE and 50CE, and 30LD and 50LD was 0.4 to 0.5%, and 0.2%, but control was 2.7%. Firmness in film packages was higher than that of control, and CE packagings were higher than LD. Total ascorbic acid content of Fuji apple in control after 75 days was 2.12 mg%, that of control was decreased by 42%, those of LD packagings were 31% and 29%, and those of CE were 24% and 22%. Titratable acidity and soluble solids content in control changed more than that of MA film packagings. Overall appearence of 'Fuji' apples in CE packagings was better than that of control.

• Journal of the Korean Chemical Society
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• v.38 no.10
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• pp.705-709
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• 1994

The kinetics of the oxidation reaction of malonic acid by ceric ion in 1 M sulfuric acid solution at $20^{\circ}C$ have been investigated by spectrophotometric method. The reaction rate at a large excess of malonic acid was found to be pseudo-first order. The observed pseudo-first order rate constants, $k_{obs}$, are dependent on the concentration of malonic acid, [MA], of which relationship has been found to be $k_{obs}$ = (0.592[MA])/(1+14.5[MA]$^2$). A mechanism for the reaction has been suggested on the basis of the above rate equation. The rate determining step may be the electron transfer reaction between enolate type malonate anion, which is formed by the acid dissociation reaction of malonic acid, and Ce(IV). The rate depression in the range of high concentration of MA has been explained by the formation of 1 : 2 chelate between Ce(IV) and malonate. According to the mechanism, the pH dependence of the rate, which was studied by Sengupta et al., has also been explained.

• Food Science and Preservation
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• v.5 no.4
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• pp.331-334
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• 1998

Weight loss of table Grape packed with control(Corrugated paperboard box), LDPE, CE(MA film masterbatched by ceramic powder treated cemical reagent) and FC box(laminated by CE film pouch) at 25 C after 10 days were 5.6%, 0.4%, 0.6%, and 0.7%, respectively. Weight loss of control was 7.29times higher than that of FC box. Total ascorbic acid content(TAA) of table grape after 10 days was 3.42 mg% for control, was 5.33 for LDPE and 5.14mg% for CE, 4.98mg% for FC. TAA of LDPE and CE showed to higher than that of control, especially TAA of FC was 33% higher than that of control. Titratable acid of LDPE and CE was high compare to control, and acidity of FC was 6% higher than that of control. References in overall appearance of LDPE, CE and FC were better than that of control. Corrugated paperboard box(FC) laminated with functional MA film showed to be able to used as packaging box of table grape.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.7 no.2
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• pp.1-5
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• 2001

This study was measured weight loss, total ascorbic acid, titratable acidity, and soluble solids content and overall appearances to investigate the effect of FC(corrugated fiberboard box laminated with functional MA film)box, LDPE film, CE(functional MA film)pouches and double wall corrugated fiberboard box during storage at $20^{\circ}C$. Weight loss of tomato packed with control, LDPE, CE and FC box at $25^{\circ}C$ after 7 days were 5.3%, 1.5%, 1.3%, and 1.5%, respectively. Weight loss of control was 3.8% higher than that of FC box. Total ascorbic acid content(TAA) of tomato after 7. days, control was 6.89 mg%, LDPE was 8.62 and CE was 8.53mg%, FC was 8.42mg%. TAA of LDPE, CE and FC was higher than that of control. Titratable acidity of tomato packed with LDPE, FC and CE was higher than that of control. Overall appearances of tomato packed with LDPE, CE and FC was better than that of control. Functional MA film laminated in corrugated paperboard box(FC) showed to be able to used as a packaging box of tomato.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.330.2-330.2
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• 2014

III-V족 화합물반도체는 트랜지스터와 광다이오드, 레이저 등의 광전소자 제작물질로 오랫동안 사용 되어 왔다. III-V 화합물 반도체로 제작된 광전소자의 특성을 향상시키기 위해선 다양한 형태의 표면구조가 필요하며, distributed feedback 레이저나 distributed Bragg reflector 레이저의 경우 높은 aspect-ratio를 가지는 구조를 필요로 한다. 현재까지 높은 aspect-ratio를 가지는 III-V족 화합물반도체 구조제작을 위해 reactive ion etching (RIE) 방식을 사용 하였는데, 이 방법은 ion collision에 의한 표면손상과 더불어 에칭 잔여물이 남아 반도체 표면을 오염시키는 문제점을 가지고 있다. 이를 개선하기 위하여 MaCE (Metal-Assited chemical etching)법이 최근 제안되었는데, 본 연구에서는 MaCE 방법을 통하여 다양한 형태의 GaAs 표면구조를 제작하였다. 본 실험을 통하여 에칭용액 조건에 따라 GaAs의 구조적 특성과 morphology가 달라지는 것을 확인하였다.

• Horticultural Science & Technology
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• v.18 no.1
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• pp.18-21
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• 2000

This study was carried out to investigate the MA response of fresh lemongrass (Cymbopogon citratus) depending upon film sources and storage temperatures. The fresh weight loss was significantly lower at 5 and $0^{\circ}C$ than those of higher temperatures. And ceramic $80{\mu}m$ film (CE 80) was more effective in preventing weight loss than CE40. The contents of $CO_2$ and ethylene were much higher in CE 80 wrapping than those in CE 40 ones. Rapid accumulation of $CO_2$ was observed at high storage temperature. However, the ethylene content during whole storage period was higher at $0^{\circ}C$ than those at $5^{\circ}C$, but the level of ethylene was remained below 1ppm and did not adversely affected to lemongrass quality. The treatment of CE 80 at $5^{\circ}C$ was most effective on keeping visual quality and chlorophyll content. The storage durations were up to 48 days at $5^{\circ}C$ and 35 days at $0^{\circ}C$, respectively. Results indicated that CE 80 at $5^{\circ}C$ is an optimal condition for MA storage of lemongrass.

• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.105-111
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• 2012

Manganese (Mn) catalysts were generated using $CeO_2$ and $ZrO_2$supports synthesized by the supercritical hydrothermal method and two different Mn precursors, aimed at an application for a low-temperature selective catalytic reduction process. Manganese acetate (MA) and manganese nitrate (MA) were used as Mn precursors. Effects of the kind and the concentration of the Mn precursor used for catalyst generation on the NOx removal efficiency were investigated. The characteristics of the generated catalysts were analyzed using $N_2$ adsorption-desorption, thermo-gravimetric analysis, X-ray diffraction, and X-ray photoelectron spectroscopy. De-NOx experiments were carried out to measure NOx removal efficiencies of the catalysts. NOx removal efficiencies of the catalysts generated using MA were superior to those of the catalysts generated using MN at every temperature tested. Analyses of the catalyst characteristics indicated that the higher NOx removal efficiencies of the MA-derived catalysts stemmed from the higher oxygen mobility and the stronger interaction with support material of $Mn_2O_3$ produced from MA than those of $MnO_2$ produced from MN.

• Food Science and Preservation
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• v.5 no.4
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• pp.335-338
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• 1998

Weight loss of fear packed with corrugated paperboard box(FC) laminated with functional MA film after 60 days storage at 5$^{\circ}C$ was 1.0%, and that of LDPE, CE film was 0.6-0.7%, while that of control(Corrugated Paperboard box) was 2.8%. Total ascorbic acid content of pear ill MA films and FC package was higher than that of control. Titratable acid of control changed 37%, but that of the others packages changed below 27%. Soluble solid content of control changed 27%, while the others changed below 2%. Reference in overall appearence of pear were not found among packaging methods. Corrugated paperboard box(FC) laminated with Functional MA film can be used as packaging material for pear packaging.

• Bulletin of the Korean Chemical Society
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• v.11 no.2
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• pp.154-156
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• 1990

The alternating copolymers of dihydropyran(DP)-maleic anhydride(MA), dihydrofuran(DF)-MA and DF-vinylene carbonate(VC) were prepared by free radical copolymerization of DP or DF with MA or VC. The reactivity ratios for poly(DF-VC) were found to be less than unity (0.05, 0.04) and its alternating sequences were obtained by feeding an equimolar amount of the comonomers at the onset of copolymerizations. The copolymers were hydrolyzed to give poly(TP-CE), poly(TF-CE) and poly(TF-HE), whose cytotoxicities against normal and tumor cells (3LL, B16) were measured in vitro.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2148-2150
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• 2014